713 

U. S. DEPARTMENT OF AGRICULTURE. 

OFFICE OF EXPERIMENT STATIONS, 
I A. C. TRUE, Director. 



INVESTIGATIONS 



NUTRITION OF MAN 



IN THE 



UNITED STATES. 



C. F. LANGWORTHY, Ph. D., and R. D. MILNER, Pii. B. 

Of the Office of Experimeni Statiom^. 




WASHINGTON: 

GOVERNMENT PRINTING OFFICE. 
1904. 



LIST OF PUBLICATIONS OF THE OFFICE OF EXPERIMENT STATIONS ON 
THE FOOD AND NUTRITION OF MAN. 



E. — For those publications to which a price is aflixoil application should be made to the Super- 
lent of Documents, Government Printing Office, Washington, I). C, the oflflcer designated by 



KOTE.- 

intenden 

law to sell Government publications. Publications marked with an asterisk (*) are not available for 

distribution. 



♦Charts. Food and Diet. By W. O. Atwater. (Four charts, 26 by 40 inches.) Price per set, 

unmounted, 75 cents. 
*Bul. -Jl. Methods and Results of Investigations on the Chemistry and Economy of Food. By W. O. 

Atwater. Pp. 222. Price, 15 cents. 
Bui. 2S. (Kevisud edition.) The Chemical Composition of American Food Materials. By W. 0. 

Atwater and A. P. Bryant. Pp. 87. Price, 5 cents. 
Bui. 29. Dietary Studies at the University of Tennessee in 1895. By C. E. Wait, with comments by 

W. ()! Atwater and C. D. Woods. Pp. 45. Price, 5 cents. 
Bui. 31. Dietary Studies at the University of Missouri in 1895, and Data Relating to Bread and Meat 
" Con.-i'umption in Missouri. By H. B. Gibson, S. Calvert, and D. W. May, witli comments by 

W. O. Atwater and C. D. Woods. Pp. 24. Price, 5 cents. 
*Bul. 32. Dietary Studies at Purdue Univensitv, Lafayette, Ind., in 1895. By W.E.Stone, with com- 
ments bv W. O. Atwater and C. D. Woods. Pp. 28. Price, 6 cents. 
Bui. 35. Food and Nutrition Investigations in New Jersey in 1895 and 1890. By E. B. Voorhees. Pp. 40. 

Price, 5 cents. 

* Bui. 37. Dietary Studies at the Maine State College in 1895. By W. H. .Jordan. Pp. 57. Price, 5 cents. 

Bui. 3H. Dietary Studies witli Reference to the Food of the Negro in Alabama in 1.895 and 1S96. Con- 
ducted with the cooperation of the Tuskegee Normal and Industrial Institute and the Agri- 
cultural and Mechanical College of Alabama. Reported by W. O. Atwater and C. D. Woods. 
Pp. 69. Price, 5 cents. 

Hul. 10. Dietary Studies in New Mexico in 1895. ByA. Goss. Pp.23. Price, 5 cents. 

Bui. 13. Losses'in Boiling Vegetables and the Composition and Digestibility of Potatoes and Eggs. 

By. H. Snyder, A. .7. Frisby, and A. P. Bryant. Pp. 31. Price, 5 cents. 
Bui. 41. Report of Preliminary Investigations on the Metal)olism of Nitrogen and Carbon in the 

Human Organism with a Respiration Calorimeter of Special Construction. By W. O. 

Atwater, CD. Woods, and F. G. Benedict. Pp. 64. Price, 5 cents. 
Bui. 15. A Digest of Metabolism Experiments in which the Balance of Income and Outgo was 

Determined. By W. O. Atwater and C. F. Laugworthy. Pp. 434. Price,- 25 cents. 
*Bul. 16. Dietary Studies in New York City in 1895 and 1896. By W. O. Atwater and C. D. Woods. 

Pp. 117. Price, 10 cents. 
Bui. .52. Nutrition Investigations in Pittsburg, Pa., 1894-1896. By Isabel Bevier. Pp. 48. Price, 

5 cents. 
Bui. .53. Nutrition Investigations at the University of Tennessee in 1896 and 1897. By C. E. Wait. 

Pp. 10. Price, 5 cents. 
*Bul. 54, Nutrition Investigations in New Mexico in 1897. By A. Gos.s. Pp.20. Price, 5 cents. 
Bui. 65. Dietary Studies in Chicago in 1S95 and 1896. Conducted with the cooperation of Jane 

Addams and Caroline L. Hunt, of Hull House. Reported by W. O. Atwater and A. P. 

Bryant. Pp.76. Price, Scents. 

* Bui. ,56. His'tory and Present Status of Instruction in Cooking in the Public Schools of New York 

City. "Reported by Mrs. Louise E. Hogan, with an introduction by A. C. True, Ph.D. 
Pp. 70. Price, 5 cents. 
Bui. 63. Description of a New Respiration Calorimeter and Experiments on the Con.servation of Energy 
in the Human Body. By W. O. Atwater and E. B. Rosa. Pp. 94. Price, 10 cents. 

* Bui. 6C. The Physiological KiTect of Creatin and Creatinin and their Value as Nutrients. By J. W. 

Mallet. Pp.24. Price, 5 cents. 
Bui. 67. Studies on Bread and Bread Making. By Harry Snyder and L. A. Voorhees. Pp. 51. Price, 

10 cents. 
Bui. 68. A Description of Some Chinese Vegetable Food Materials and Their Nutritive and Economic 

Value. By W. C. Blasdale. Pp. 48. Price, 10 cents. 
B)il. 69. Experiments on the Metabolism of Matter and Energy in the Human Body. By W. O. 

Atwaterand F. G. Benedict, with the cooperation of A. W. Smithand A. P. Bryant. Pp.112. 

Price, 10 cents. 
Bui. 71. Dietary Studies of Negroes in Eastern Virginia in 1897 and 1898. By H. B. Frissell and Isabel 

Bevier. Pp. 45. Price, 5 cents. 
Bui. 7.5. Dietary Studies of University Boat Crews. By W. 0. Atwater and A. P. Bryant. Pp. 72. 

Price, 5 cents. 
Bui. 84. Nutrition Investigations at the California Agricultural Experiiment Station, 1896-1898. By 

M. E. Jaffa. Pp. 39. Price, 6 cents. 
Bui. 85. A Repr)rt of Investigations on the Digestibility and Nutritive Value of Bread. By C. D. 

Woods and L. H. Merrill. Pp. 51. Price, 5 cents. 

[Continued on third page of cover.] 



U. S. DEPARTMENT OF AGRICULTURE, 

l\.S. OFFICE OF EXPERIMENT STATIONS, 

A. C. TRUE, Director. 



1 



INVESTIGATIONS 



NUTRITION OF MAN 



IX THE 



UNITED STATES. 



BY 



C. F. LANG WORTHY, Ph. D., and R. D. MILNER, Ph. B., 

OJ tlie Office of Exjie7'i7nen1 Staticnts. 




WASHINGTON: 

GOVEKNMENT PRIXTIXG OFFICE. 
19 04-.; 



6^^ 



> ,' 3 3 3 3 



OFFICE OF EXPERIMENT STATIONS. 

A. C. True, Ph. D., Director. 

E. W. Allen, Ph. D., Assistant Director and Editor of Kvperime)tt Statio)i Record. 

C. F. L.\X(;woRTHY, Ph. I)., Editor and Expert on Foods and Aiiimal Production. 

NUTRITION INVESTIG.\TIONS. 



W. O. Atwater, Ph. D., Chief of Xulrition Invesiif/ations, Middletovn, Conn. 

C. D. Woods, B. S., Special Agent at Orono, Me. 

F. G. Benedict, Ph. D., PlHjdological Chemist, Middleiown, Conn. 

R. D. INIiLNER, Ph. B., Editorial Assistant, MiddJetoicn, Conn. 



LETTER OF TRANSMITTAL. 



U. S. Department of Agriculture, 

Office of Experiment Stations, 

Washington^ D. 6'., May 25^ 190 Jf.. 
Sik: I have the honor to transmit herewith and recommend for pub- 
lication a summary showing- the scope of the cooperative nutrition 
investigations carried on under the auspices of this Otiice. This 
includes an account of the origin and development of the investiga- 
tions and their character, data regarding the collaborators and collab- 
orating institutions, and also some of the more important results 
obtained. 

Respectfully, A. C. True, 

Dinctor. 
Hon. James Wilson, 

Sccreta ry of A <j rlcult u re. 



CONTENTS. 



Introduction 

Organization of the in(|uiry 

Scope of the incjiiiry 

Distribution of tlie work 

Some results of nutrition investigations 

Composition of food materials 

Dietary studies 

Digestion experiments 

Metabolism experiments with the respiration calorimeter 

Factors for digestibility and fuel value of nutrients 

The pecuniary economy of food 

The educational influence of the nutrition investigations 

Conclusion 



Page. 



8 
10 
12 
12 
13 
10 
16 
17 
18 
19 
20 



ILLUSTRATIONS. 



Plate I. Fig. 1. — Bread from normal tiour and from mixtures of normal and 
extracted flours. Fig. 2. — Bread from normal flour and from 

mixtures of normal and corn flours 8 

II. Composition of food inaterials 12 

III. Dinner at a Chiuese truck farm, California 12 

IV. ( ieneral view of the respiration calorimeter 16 

V. (iround plan of respiration calorimeter laboratory 16 

VI. Pecuniary economy of food 18 

4 



INVESTIGATIONS ON THE NUTRITIOX OF MAN IN THE 
UNITED STATES. 



By C. F. Lang WORTHY, Ph. D., and R. D. Milxer, Ph. B., 

Of the Office of Experiment Stations. 



INTRODUCTION. 

During- the past few years the experimental study of the food and 
nutrition of both dome.stie animals and man has become verj^ active in 
the United States. A large part of such inquiry, indeed nearly all of 
that which has to do with domestic animals, is carried on in connec- 
tion with the agricultural experiment stations, which have been estab- 
lished within the past twenty-eight years and are now in operation in 
all the States and Territories of the Union except the Philippines. 

With the rise of the experiment stations inquiries into the composi- 
tion of feeding stutfs and their appropriate use in the nutrition of 
domestic animals were undertaken, and have ever since been carried 
on quite actively. Later some of the stations undertook similar inves- 
tig'ations of tlie food of man, and in recent years the study of the food 
and nutrition of man has acquired increased importance in the United 
States from the extensive investigations that have been made and are 
still being made in connection with and as a part of the work of the 
Department of Agriculture in cooperation with universities, colleges, 
experiment stations, benevolent institutions, and individual investi- 
gators in different parts of the country. 

There had been, indeed, a considerable amount of study of the food 
of man — and of domestic animals also — before the experiment stations- 
were established. An interesting investigation on the subject of 
human nutrition was prosecuted b}- J. R. Young, in Philadelphia, as 
early as 1803, and perhaps almost continuously since that time vaki- 
able information on food and nutrition has been accumulated by phy- 
sicians, by State boards of health, and b}^ .specialists in physiology, 
hygiene, and dietetics. The United States Government, through its 
various branches, has contributed much of value to the science of 
nutrition. The War Department and the Navy Department, in their 
efforts to secure the most satisfactory diet for the soldiers and sailors, 
have collected a great deal of information and conducted man}^ inves- 
tigations which have to do with the subject of dietetics, while the 

5 



6 

importance of their investigations dealing- with the hygiene of the 
subject can hardl}' be overestimated. In connection with the United 
States Census a large amount of data regarding foods has been 
secured, the major portion of which has to do with production and 
distribution, though man}' analyses have been reported in census pub- 
lications, as well as special studies of foods, food industries, and 
related topics. Of ver^^ noteworthy importance are the studies of 
analytical methods, of the chemical composition of foods, and of food 
adulteration, conducted in the Bureau of Chemistry of the Department 
of Agriculture by its chief. Prof. H. W. Wiley, and others. 

A complete historical review of investigations on food and nutrition 
of man in the United States would necessarily include an account of 
the above inquiries and others not referred to here. The purpose of 
the present article, however, is to give a brief resume of the coopera- 
tive inquiry into the food and nutrition of man now being carried on 
under the auspices of the Office of Experiment Stations of the Depart- 
ment of Agriculture, and to indicate the progress and results of that 
enterprise. This inquiry had its inception in a studv of the chemical 
composition of food fishes and invertebrates undertaken bv Prof. 
W. O. At water in 1877 and continued until 1882, in the chemical labora- 
tory of Wesleyan University, Middletown, Conn., at the instance of 
Prof. S. F. Baird, Secretar}' of the Smithsonian Institution and United 
States Commissioner of Fish and Fisheries. In connection with this 
work similar investigations of other animal and some vegetable prod- 
ucts were undertaken a little later (1884) on behalf of the United 
States National Museum. About the same time (1886) the first 
extended inquiry into the statistics of food consumption in the United 
States was undertaken b}' Hon. Carroll D. Wright, as chief of the 
Massachusetts Bureau of Statistics of La])or, and the chemical results 
were computed and reported b}- Professor At water. In 1890 the 
Connecticut (Storrs) Experiment Station, under the direction of Pro- 
fessoi" Atwater, in cooperation with Hon. Carroll I). Wright as United 
States Commissioner of Labor, began a series of dietarj- studies which 
continued for several A^ears. Except for the inquiries under the aus- 
pices of the Massachusetts lal)()»- bureau, the United States Department 
of Labor, and the Connecticut (Storrs) Experiment Station, the larger 
share of the expenses of this work w'as borne by private individuals. 
The results of these iiupuries gradually attracted attention. The 
bearing of such research upon household, agricultural, and national 
economics became evident, and as early as 1890 steps were taken to 
secure an appropriation fi'om Congress to enlarge its scope and use- 
fulness, ))ut nothing definite was accomplished there until 1891. In 
that j'ear the experiment stations were authorized by Congress to 
cooperate with the Secretary of Agriculture in studying the food and 
nutrition of man, and were called upon to report to him the results of 



« 



II 



such investigations as they might cany out. At the same time Con- 
gress provided an especial appropriation to enable the Secretary of 
Agriculture to prosecute inquiries in this direction. The sums pro- 
vided by Congress for nutrition investigations for the Department of 
Agriculture have been since the beginning: 





Fiscal 


year. 


Amount. 




Fiscal 


year. • 


Amount. 


1894-95 .... 






SIO, 000 
15, 000 
15. 000 
15,000 
15, 000 
15,0C0 


1900-1901 

1901-2 . . - - - - --^ 


S17, 500 
20, 000 


189fi-97 

jxq7 Q8 


1902-3 

1903-4 






20, 000 
20 000 


1898-99.... 
1899-1900 


1904-5 






20. 000 











These amounts have been increased by contributions from other 
sources which are not easily estimated in terms of mone\% since they 
consist in large part of the use of laboratories, apparatus, and other 
facilities for research, the counsel and help of experts, and other gra- 
tuitous service. The State of Connecticut makes an annual appropri- 
ation, which is used under Professor Atwater's direction, for nutrition 
investigations, in cooperation with the United States Department of 
Agriculture. Part of the appropriation made liy the State of Illinois 
to its State University and experiment station is regularly expended 
in the study of problems related to the food and nutrition of man. A 
considerable number of other experiment stations, educational institu- 
tions, philanthropic organizations, and private individuals have given 
sums of money to promote the cooperative inquiry. 

ORGANIZATION OF THE INaUIRY. 

The nutrition investigations of the Department of Agriculture are 
conducted through the Office of flxperiment Stations, the general 
supervision of these investigations having been assigned 1)}^ the Sec- 
retary of Agriculture to that Office. The immediate supervision of 
the enterprise has ])een entrusted to Prof. "W. O. Atwater. chief of 
nutrition investigations. 

For many years I'rofessor Atwater, in connection with his duties as 
professor of chemistiy at We.sle3an University, has devoted much of 
his time to investigations relating to the nutrition of man, introducing 
into the United States the German methods of studying nutrition 
problems. He was the iirst director of the Office of Experiment Sta- 
tions, and, after his services in this capacity had terminated, the Depart- 
ment was veiy fortunate in securing his cooperation as special agent 
in charge of its nutrition investigations. The very great development 
of this enterprise, as evidenced by the numl)er and extent of the inves- 
tigations carried on, the public interest which has been arou.sed, the 
demand for information from private individuals, physicians, and 
teachers, and the practical application of the results already obtained 



in numerous instances where rational and economical feeding- was 
a necessity, are indications that the investigations have been well 
managed. 

The administrative and editorial work connected with the nutrition 
investigations is conducted at Washington, D. C, and Middletown, 
Conn. The investigations themselves are prosecuted in different 
places, the general policv being to make particular institutions centers 
of iuA'estigations along special lines. Part of the fund provided b}" 
Congress is expended under the sole and immediate care of the Depart- 
ment; part is distributed among scientific, educational, and philan- 
thropic institutions in various places from Maine to California, and 
used not so nuich as compensation for services as for encouragement 
to research. The cooperating institutions have in most cases contrib- 
uted material assistance, especially as regards laboratory rooms and 
appliances and the services of skilled investigators. 

SCOPE OF THE INaUIRY. 

Investigations on the food and nutrition of man include the study 
of two branches of the subject, which, though quite intimately related 
and both A^aluable, are nevertheless of importance in different ways. 
One branch comprises a study of the chemical composition of dif- 
ferent food materials, an investigation that is purely anal3"tical, but a 
necessarj'^ preliminary to studies in the other branch of the subject, 
which comprises researches into the laws of nutrition. The former is 
concerned simply with the chemistry of food, while the latter has to 
do with the physiology, the~ph3^sics and chemistry, of the nutrition of 
man, together with the economic and sociological application of the 
fundamental principles of nutrition to the diet of persons in different 
localities and under different conditions in life. 

The cooperative nutrition investigations include studies of several 
branches of the subject, especial attention having been paid to studies 
of the kinds and amounts of food consumed by individuals, families, 
institutions, etc.; experiments on the digestibditv of food materials; 
and researches into the fundamental laws of nutrition, including par- 
ticularly investigations with the bond) calorimeter and the respiration 
calorimeter. In addition to these, collateral questions of a wide 
variety have also received much attention. A brief statement of the 
general lines along which the inquiries have been conducted is as 
follows: 

Studies of acUial dietaries in order to learn the kinds, anidunts, antl costs of food 
materials consumed by persons in different localities, of different occupations, ages, 
and sex, and under varying conditions. 

Special studies of cereal j^rodurts, including nutritive value of different milling 
products of wheat; nutritive value, quality, and digestibility of bread from hard and 
soft wheat flours of different grades, as "graham," "entire wheat," and 'standard 
patent" grades; bakery experiments to determine the cost of making bread, and the 



U. S. Dept. of Agr., Office of Expt. Stalions, 713. 



Plate I. 




Fig. 1 .—Bread from Normal Flour and from Mixtures of Normal and 
Extracted Flours. 

A, Normal flour; B, flour witli iibout one-half of the gliadin extracted: (', one-half normal and 
one-half gliadin-extracted flour. 




FiQ. 2.— Bread from Normal Flour and from Mixtures of Normal and Corn 

Flours. 

A, Normal flour; B, normal flour and '20 per cent corn flour: C, normal flour and 10 per cent 

corn flour. 



9 

looses in nutritive value during the process of bread making. Plate I illustrates 
the results obtained in some of these studies of the effect and the importance of the 
various constituents of flour upon the character of the bread. In fig. 1, bread A 
was made from normal fiour and breads B and C from flour which contained abnor- 
mal amounts of gliadin, one of the important nitrogenous constituents of flour. In 
fig. 2, A represents normal bread and B and C bread made from flour in which the 
starch content was rendered abnormal ))y adding corn flour. 

Special studies of meats, including the nutritive value of raw and cooked meats; 
the relative digestibility of meats cooked in different ways; the nature and amount 
of losses occurring during the cooking of meats in different ways. 

Experiments on the digestibility of vegetal)les and the losses in different vegetal)les 
during cooking. 

Experiments on the digestibility and nutritive value <>f legumes, including ])eans 
and cowpeas. 

Studies of the comparative econoniy, digestibility, and nutritive value of fruits and 
nuts. 

A convenient and comparatively inexpensive form of bomb calorimeter has been 
developed and is used in determining the amounts of potential energy in food mate- 
rials, excretory products, and other substances. 

Metabolism experiments have l>een carried on with men in the respiration calo- 
rimeter. The oV)jects of these investigations have lieen: To develop an apparatus 
and method for the accurate measurement of the income and outgo of the animal 
organism as expressed in terms of matter and energy; to confirm the belief that the 
law of the conservation of energy obtains in the living body; and, after such demon- 
stration of the accuracy of the apparatus and methods and of the action of the law of 
the conservation of energy, to study some of the more important fundamental laws 
of nutrition. 

The fact was early recognized that compilations and summaries of the investiga- 
tions which have been carried on in Europe and this country were neces.sary. In 
order to conduct any kind of research most efficiently it is necessary to know what 
has been accomplished by others in order that the investigator may profit by their 
results and that an unnecessary duplication of effort may Ije avoided. Furthermore, 
summaries of previous investigations are of great value in suggesting lines of research 
and in awakening the interest of investigators by showing past achievements. To 
this end the current literature of the nutrition of man, w-hich is now quite volumi- 
nous, is being regularly followed up, and such abstracts and compilations are being 
made as will promote the intere.st of the investigations. 

The rapid accumulation of material which must l)e made ready for publication 
necessitates a large amount of editorial work. The results of the investigations are 
given in bulletins, some of popular nature and others technical in character. The 
results of analyses of food materials in the United States have been compiled and 
printed m a bulletin for popular use, Avhich is revised from time to time as data 
accumulate. The results of dietary studies also appear in bulletins prepared for 
popular use. The data of the digestion experiments and those obtained in investi- 
gations with the respiration calorimeter are given in bulletins more or less technical 
in character, and intended rather for the scientific student of the subject. Abstracts 
of the current literature of the subject of food and nutrition appear regularly in the 
Experiment Station Record. More popular abstracts of some of this work, particu- 
larly that of American investigators, appear in the series of Farmers' Bulletins, 
entitled "Experiment Station Work." 

The correspondence connected with the nutrition investigations has grown to very 
considerable dimensions. 



10 

DISTRIBUTION OF THE WORK. 

The following is a brief snmmaiy, alphabeticalh' bj' States, of the 
localities in which the inquiries have been prosecuted, the cooperating 
institutions and investigators, and the nature of the investigations 
conducted : 

Alahmna. — Tnskegee Normal and Agricultural InstiUite; Prof. Booker T. Wash- 
ington. Alabama Polytefhnic Institute and the Alabama Experiment Station, 
Auburn; Prof. B. B. Ross. Study of the food consumption of the negroes in the 
"black belt" of Alabama, and of the character and nutritive value of the food 
materials used by negroes. 

California. — University of California; Prof. M. E. Jaffa. Cost and nutritive value of 
California food materials, especially fruits and nuts; dietary studies of infants, 
athletes, professional men, fruitarians, and Chinese; digestion and nitrogen meta- 
bolism experiments with an infant and with fruitarians. 

In addition, INIr. W. C. Blasdale, instructor in chemistry at the university, made a 
detailed study of the nutritive and economic value of Chinese vegetal)le food materials 
found in the markets of San Francisco. 

Comiedicut. — Wesleyan University and Storrs Experiment Station; Prof. W. O. 
Atwater, Prof. F. G. Benedict, and associates. Cost and nutritive value of various 
food materials; dietary studies; digestion and nitrogen metabolism experiments; 
development of bomb calorimeter and respiration calorimeter, and of methods of 
using these in investigations of the metabolism of matter and energy in the human 
body. 

The work of the office of Professor Atwater, who is chief of the nutrition investi- 
gations, has also included the planning and direct supervision of the cooperative inves- 
tigations in different parts of the country, the compilation of the results of nutrition 
investigations in the United States and foreign countries, editorial work in the prepa- 
ration of the reports of the eooperators for publication, and a large correspondence 
relating to the investigations. 

Georgia. — University of Georgia; Dr. H. C. White. Dietary studies of t-ollege 
boarding, clubs, and of families in the mountain regions of Georgia. 

Illinois. — Hull House, Chicago; ISIi.ss Jane Addams and ISIiss Caroline Hunt; and 
Lewis Institute, Chicago; Prof. G. N. Carman. Dietary studies. 

]Mrs. Ellen H. Richards and Mi.ss Amelia Shapleigh also carried on dietary studies 
with the cooperation of Hull House. The data obtained were eventually submitted 
to the Department of Agriculture for calculation and publication. 

University of Illinois; Prof. H. S. Grindley. Cost and nutritive value of food 
materials; dietary studies: special investigations on meat, including losses in different 
modes of cooking, and digestibility of meats cooked in different ways. Prof. Isabel 
Bevier and Miss Elizabeth Sj)rague. Studies in cooking meat. • 

Indiana. — Purdue University; Prof. W. E. Stone. Dietary studies. 

Maine. — University of Maine and ]\Iaine p]xi)eriment Station; Prof. W. H. Jordan, 
Prof. C. D. AVoods, and L. H. Merrill. Studies of the nutritive value of a number 
of food materials; feeding experiments to determine the value oi milk in the diet; 
and dietary studies and digestion experiments, especially with lumbermen in the 
Maine woods. Experiments on the digestibility and nutritive value of bread made 
from different grades of flour; study of experimental methods, particularly means of 
separation of feces in digestion experiments and determination of metabolic nitrogen 
in feces. 

Maniknah — Mrs. Mary Hinnian Abel cooperated with the D('i)artiuent in the 
l)rei)aration of summaries of data regarding the nutritive value and ]>]ace in theMiet 
of sugar and of leguminous vegetables, and in connection with this work made a 
number of cooking experiments. 



11 

^fassac)^vselt.t. — School of Housekeeping, Boston; Miss Lydia Southard, Miss 
Susannah Usher, and INIiss Bertlia M. Terrill carried on dietary studies, in a number 
of which the attempt was made to regulate»the cost of the food and at the same time 
make it compare with commonly accepted dietary standards. The results of these 
investigations were submitted to the Department for calculation and publication. 

Harvard University, Cambridge; Dr. E. A. Darling. Dietary studies of athletes. 
Prof. C. R. Sanger and Mr. Edward INIallinckrodt, jr. Dietary studies of students. 

Springfield Bible Normal College; Miss Bertha M. Terrill. Dietary study. In 
this investigation the attempt was made to regulate the cost of the daily food and at 
the same time make it correspond with the connnonly accepted dietary standards. 
The results were submitted to the Department for calculation and publication. 

Minnesota. — University of Minnesota and Minnesota Experiment Station; Prof. 
Harry Snyder. Study of losses in cooking vegetables and in making bread; special 
studies of cereal products, including relative nutritive value of milling products of 
wheat, and digestibility and nutritive value of bread made from different grades of 
hard and soft wheat flours. A considerable part of the latter investigation is carried 
on coordinately with similar work by Prof. C. D. Woods at the Maine Experiment 
Station. 

Missouri — University of Missouri; Prof. H. B. Gibson. Dietary studies; inve.sti- 
gation of the relative consumption of different kinds of meat and liread. 

New Jersey. — New Jersey Experiment Station; Prof. E. B. Voorhees and Mr. L. A. 
Voorhees. Dietary study; studies of the cost and comijosition of milk and of bread, 
of the relative cost of bread and the raw ingredients from which it was made, and of 
the losses in baking bread. 

Neiv Mexico. — New Mexico College of Agriculture and Mechanic Arts and New 
Mexico Experiment Station; Prof. Arthur Goss. Stu<ly of the relative nutritive 
value of native food materials, especially native beef, and of the food consumption of 
native Mexican families. 

New York. — -Mrs. Louise E. Hogan studied the history and methods of teaching 
cookery in the public schools of New York City. 

Cornell University, Ithaca; Prof. R. C. Carpenter. Mea.surements of mechanical 
work, and studies of the efficiency of man as a machine. 

New York Association for the Improvement of the Condition of the Poor and New 
York Christian Alliance, New Y''ork; Dr. Isabelle Delaney. Dietary studies of poor 
families in congested districts in New York City. 

Columbia University, New Y^ork; Dr. H. C. Sherman. Digestion experiments and 
investigations on the metabolism of nitrogen, sulphur, and phosphorus in the human 
])ody. 

North Dakota. — North Dakota Agricultural College; Prof. E. F. Ladd. Dietary 
study. 

Ohio. — Lake Erie College; Prof. Isabel Bevierand ^liss Elizabeth Sprague. Dietary 
study. 

Pennsylvania.— College Settlement, Philadelphia; Mrs. Ellen H. Richards and Miss 
Amelia Shapleigh. Dietary studies of families of limited income Avere undertaken, 
the data obtained being submitted to the Department for calculation and publication. 

Pennsylvania College for Women, Pittsburg; Prof. Isabel Bevier. Dietary studies; 
study of the composition and cost of bakers' liread in Pittsburg and of the changes 
in the materials of bread during baking. 

Tennessee. — University of Tennessee; Prof. C. E. Wait. Analyses of Tennessee 
food materials; dietary studies; experiments on the effect of muscular work ujion 
the digestibility of food and the metabolism of nitrogen; studies of the digestibility 
and nutritive value of legumes. 

T>rmo»/.— Vermont Experiment Station; Prof. J. L. Hills. Dietary studies of 
farmers' families. 



12 

Virginia. — Hampton Normal and Agricultural Institute; Dr. H. B. Frissell. Dietary 
studies of negroes. 

Under special authorization Miss Isabel Bevier also made similar studies in another 
part of the State. 

State University; Prof. J. W. ^Mallett. Studies uf the physiological effects of meat 
bases, i. e., creatin and creatinin. 

Washington, D. C. — Besides the general supervision vi the plans and expenditures, 
the work of the Washington office in relation to the nutrition investigations has 
included the preparation of popular bulletins; the compilation of technical summa- 
ries of investigations; editorial work in perfecting the details of reports of investiga- 
tions; collection of bibliographical data; the abstracting of the literature of nutrition, 
partly for pul)lication in the Experiment Station Record; the conducting of a large 
correspondence growing out of nutrition investigations, and the distribution of pub- 
lications on this subject. This w^ork is in charge of Dr. C. F. Langworthy. 

Cooperating with the U. S. Department of the Interior a series of studies of food 
consumption has been conchicted in the Government Hospital for the Insane at 
Washington, D. C. The results obtained were interesting and valuable, and are 
being utilized to make the diet, which was found to be ample and of good quality, 
conform to theoretical requirements. This cooperative investigation was begun by 
Dr. A. B. Richardson and was continued by his successor. Dr. W. A. White, the 
experimental work having been carried on by Mr. H. A. Pratt. 

Mention should also be made here of other inve.stioations which, 
while not strictl}' a part of the cooperative inquirv, are yet .so closely 
related to it that they may be included in this summary: 

On behalf of the New York State Commission in Lunacy an extended series of 
studies of the food consumption of the New York hospitals for the insane was car- 
ried on under the supervision of Professor Atwater. 

A study of the food consumption at the Elmira Reformatory, in New York State, 
was also made under the supervision of Professor Atwater. 

A sum of money has been granted by the Carnegie Institute to Professor Atwater 
for the development of accessory apparatus and methods for determination of oxygen 
in connection with the experiments in the respiration calorimeter, and for investiga- 
tions of the income and outgo of oxygen in the animal organism. The apparatus has 
been completed and found to be very accurate (see p. 16). 

SOME RESULTS OF NUTRITION INVESTIGATIONS. 

Among the more important results obtained in these investiofations 
are tho.se from studies of the composition of food material, from 
dietary studies, digestion experiments, and investigations with the 
respiratioji calormieter. 

COMPOSITION OF FOOD MATERIALS. 

One result of the investigations of food and nutrition in the United 
States, including botii the work done as a part of the cooperative 
incjuiiy and that carried on in other connections, is that we have now 
a tolerably clear idea of the composition and nutritive values of our 
ordinal V American food materials. In the latest revised edition of a 



U. S. Dept. of Agr., Office of Expt. Stationb, 713. 



Plate II. 




PiilcsZible nutrients 



n_ _j „ J. Car-bo- MinerctV 

i^aicin Fats byoU-octct 7na.Ue.rs 



Indiy^-iAtibU nutncnti Non mitnents. 
Water Kefu.se. 



Composition of Food Materials. Nutritive Ingredients, Refuse, and Fuel 

Value. 



U. S, Dept. cf Agr., Office of Expt- Stations, 713. 



Pla-e mi. 




18 

bulletin" puhlishcd in 1903. in wliich these results are compiled, the 
total number of analyses included was 4,063. Of these, 1,618 were of 
animal foods, 2,375 of veg-etable foods, and TO of unclassified foods. 

At the present time the number of analyses thus compiled is more 
than 4,5(H) and is still rapidly increasing-. The}' are now derived 
more largely from other sources than the cooperative nutrition investi- 
gations, because in connection with the latter they are made onh' when 
necessar}', as in digestion and metabolism experiments. They are no 
longer made simplj' to increase the amount of such data available. 
Plate II shows in graphic form the composition and fuel value of some 
of the more common food materials. 

DIETARY STUDIES. 

The number of studies of the actual food consumption of people of 
dirt'erent classes that have formed part of the cooperative inquiry in 
ditferent parts of the United States is now over 500. These include 
studies of families of day laborers, farmers, mechanics, and men in 
professional life; of peoj^le in congested districts of the slums of New 
York and Chicago, and poor families in other cities; of negroes in the 
South; of Spaniards in the extreme Southwest; and of Chinese and 
fruitarians on the Pacific coast. In a large number of these studies 
actual analyses were made of food materials and of waste. In addition 
to the above, which were made entirely as a part of the cooperative 
nutrition investigations, nearly half as many studies of a similar 
nature not directly related to the cooperative inquiry have also l^een 
completed. The latter include studies in private families, in boarding- 
houses and clubs of men and women in colleges, in hospitals for the 
insane, and in other institutions. The total number of pei'sons — men, 
women, and children — included in all these studies is iK)t far from 
15,000. 

Results of some of the more important dietary studies thus far made 
are sunnuarized in the following table. These are typical of the 
studies already published. The data of a consideralile iuunl>er of 
other studies are now being prepared for publication. 

«U. S. Dept. Agr., Office of Experiment Stations Bui. 28: The Chemical Composi- 
tion of American Food Materials. Revised edition, 1903. 



14 

Summarized results of dktanj studies in the United States 
[Quantities per man per day.] 



PERSONS WITH ACTIVE WORK. 



Rowing clubs in New England 

Bicyclists in New York 

Football teams in Connecticut and Cali- 
fornia 



PERSONS WITH ORDINARY WORK. 



Farmers' families 

Mechanics' families 

La) hirers' families in large cities 

Lahiirers' families in more comfortable 
circumstances 



PROFESSIONAL MEN. 



Lawyers, teachers, etc. 
College clubs 



MEN WITH LITTLE OR NO EXERCISE. 

Men in respiration calorimeter 

PERSONS IN DESTITUTE CIRCCMSTANCES. 



Poor families in New York City 

Laborers' families in Pittsburg", Pa. 



MISCELLANEOUS. 



Negro families in Alal>ama 

Negro families in Virginia 

Italian families in ('hicago 

French Canadians in Cliicago 

Bohemian families in Cliicago 

Inhiibitantsdf .lava Village, C'olumbian 

E:xi)osition, 1893 

Russian .lews in Chicago 

Mexican families in New Mexico 

Chinese dentist in ('alifornia 

Cliinesc lanndrymeii in California 

Chinese farm lal)orers in California 

Fruitarians 



lUr.TAr.Y STANDARDS. 

Man with very hard muscular work 

f Atwater) . . .' 

Man with hard niuscularwork (Atwater) 
Man wiih niodiTately active muscular 

work (Atwater) ...". 

Man with light to moderate muscular 

work (Atwater) 

Man at "seileiitary " or woman with 

moderately active work {.\twater) 

Woman at light to uKjderate muscular 

work (Atwater) 



Actually eaten. 



Digestible. 



Gms. 
1.55 
186 



97 
103 
101 



104 

107 



62 
109 
103 
lis 

ll.T 

66 
137 

94 
115 
135 
144 

.50 



175 
150 

125 

112 

100 

90 



Gms. 
177 
186 

354 



130 
150 
116 



125 
148 



132 
1.59 
111 

1.58 
101 

19 
103 

71 
113 

76 

95 
102 



(«) 
(") 

(«) 

(") 

C) 



1 

Si 

O 


d 
'S 


Gms. 


Gms. i 


440 


143 


651 


171 


634 


208 


467 


89 


402 


95 


344 


93 


534 


110 i 


423 


96 


459 


98 


305 


103 


407 


86 


308 


74 


436 


57 


444 


100 


391 


95 


345 


109 


360 


106 


254 


61 


418 


126 


613 


86 


289 


106 


566 


124 


■ 640 


132 


237 


43 


{«) 


161 


(«) 


138 


(") 


115 


(«) 


103 ; 


(") 


92 


(«) 


83 



168 
177 



336 



124 
143 
110 



119 
141 



125 
151 
105 
150 
96 

18 
98 
67 
107 
72 
90 
92 



(") 
(") 
(«) 
(«) 
(«) 



Gins. I Cals. 
427 ' 3,955 
631 5, 005 



453 3,415 
390 I 3,355 
334 2,810 

518 3, 925 



410 3, 220 
445 3,580 



296 2, 380 



395 
299 



423 
342 
379 
335 
349 

246 
405 
595 
281 
549 
621 



(«) 
(") 
(«) 
(«) 



2, 845 
2,400 



3,165 
3, 625 
2, 965 
3. 260 

2,800 

1,4.50 
3, 135 
3, 460 
2, 620 
3, 480 
3,980 
2, 055 



5, .500 
4,1.50 

3,400 

3, 050 

2, 700 

2, 4.50 



6.6 

6 



8.2 
7.5 
6.3 



4.5 



6.9 
6.8 



12.4 
6.8 
6.5 
6. 2 
5.3 

4.7 
5 

8.7 
4.9 
5.7 
6.2 
10 



7.2 
6.2 

0.2 

6.1 

6.1 

6.1 



" Fats ai;<l carbohydrates in sufficient amounts to furnish, together with the protein, the indicated 
amuuiit of eiiergv. 



The tio'ure.s in the above tabk^ sliow l)oth the total nutrients in the 
food con.suiiied, as cak-ulated from the weij^'iit.s aiul cheinieal composi- 
tion, and the dig-e.stil)le nutrients as estimated by use of coefficients of 
digestil)ility l>a.sed upon the results of diovstion experiments. The 



15 

fuel value of the diet — i. c, the amount of energy actually available to 
the body — has been calculated by the use of the most recent factors 
for fuel value of nutrients. The table also shows dietary standards 
that have been proposed on the basis of the data obtained in dietary 
studies, digestion experiments, and investigations with the respiration 
calorimeter. 

From the results of these investigations it is apparent that varia- 
tions in diet are in part such as naturally follow differences in the actual 
food supply; but the}' are also intluenced to some extent by race habits, 
and to a still larger extent by the amount of muscular work performed 
and by the material circumstances of the consumer, including espe- 
cially his income. 

One of the most important ways in which practical application may 
be made of the results of these studies to the benetit of large numbers 
of people is in teaching the relative nutritive value of difl'erent food 
materials and their pecuniar}^ economy. Much is already being done 
in this direction in different parts of the United States. 

The proper nourishment of the inmates of institutions where large 
num))ers must be fed, such as schools, reformatories, prisons, and hos- 
pitals, is a subject that is attracting no little attention at the present 
time. In many instances dietary studies have been made in schools, 
college clubs, etc., and the information obtained has been of much use. 
That such studies have been found to have a practical value, and that 
the interest in them is widespread, is shown by the fact that a consid- 
erable number have been undertaken by instructors and others inter- 
ested, aside from those carried on by the Department of Agriculture. 
The dietar}" studies were made under widely varying conditions. Plate 
III, showing Chinese farm laborers at dinner, is an illustration of this. 
These laborers were one of the groups studied in an investigation of 
the dietary of Chinese on the Pacific coast. 

As a result of such studies as those described above, the dietary 
standards included in the table have been suggested. These are 
intended to show the actual food requirements of persons under dif- 
ferent conditions of life and work, and how these requirements may 
be most economically and efficiently supplied by the available food 
materials. It is not claimed, however, that the food each da}- should 
contain exactly the kind and amounts of the different nutrients 
required by the standards. A slight deficiency one da}^ will be made 
good l)y an excess the next, the body serving as a storehouse for 
reserve material. Experience has, however, shown that the bodj' is 
best nourished when through long periods the food approximates the 
requirements of the so-called standards. Individual requirements and 
individual peculiarities will always affect the choice of foods.. 

The exact knowledge which comes with such researches is showing 
how the diet of largo classes of our population ma}' be materially 
improved while often its cost may be considerably reduced. 



16 

DIGESTION EXPERIMENTS. 

Nearly 600 digestion experiments, mosth^ with men but a few with 
women and children, have been made in connection with the nutrition 
investigations of the Department. In connection with nearly half of 
these the income and outgo of nitrogen has been determined, thus 
making them nitrogen metabolism experiments also. 

The results of these digestion experiments show the digestibili't}- of 
various sorts of mixed diet and of individual food materials. Taking 
these results into account, together with the results of analyses, we 
are able to prepare tables showing the average quantities of digestible 
nutrients in a large numl)er of the food materials in most common use. 

METABOLISM EXPERIMENTS WITH THE RESPIRATION CALO- 
RIMETER. 

From the more purelv scientific standpoint, the interest of this 
cooperative nutrition inquiry culminates in the experiments with the 
respiration calorimeter. These have for their object the stud}' of the 
transformation of matter and energy in the living organism. In other 
words, they represent an inquiry into the most fundamental and most 
important laws of nutrition. The apparatus used for the purpose, 
known as the Atwater-Rosa respiration calorimeter, wdiich has been 
developed in connection with these investigations, suffices for the 
accurate measurement of the income and outgo of all chemical elements 
except oxygen, of the potential energy of food, of unoxidized excre- 
tory products, of body material gained or lost, and of the kinetic 
energy given otf from the body in the forms of heat and external 
muscular work. Accessory apparatus and a method for the direct 
determination of income and outgo of oxygen have very recenth' been 
completed by Professors Atwater and Benedict, and it is possible with 
the calorimeter as thus modified to determine directly all the elements 
of income and outgo and in addition to study the respiratory quotient 
which is known to be a very delicate index of the processes going on 
in the body. Plate IV gives ageneral view of the respiration calorim- 
eter, and Plate V a ground plan of the cidorinieter laboratory. 

One very important result thus far obtained by the use of this 
apparatus is what amounts practically to a demonstration that the 
law of the conservation of energy applies to the living organism. 
The proof that this law obtains in the inorganic world was one 
of the great scientific achievements of the last century. It has, of 
course, been assumed and very generally believed that it nmst also 
apply in the organic world — in the living being; but a complete 
and satisfactory demonstration has not hitherto been made, although 
an approximate proof was found in a iuim})er of European exp(>ri- 
ments with dogs. As the outcome of 04 experiments by Professors 



U. S. Dept. of Agr., Of ice of Expt. Stations, 713. 



Plate IV. 




U. S. Dept. of Agr., Office of Expt. Stations, 713. 



Plate V. 



^\^ 








1^ 


nH 


O 

-< 
z. 



< 
z 










17 

Atwater and Benedict, and their associates, at Wesleyan University, 
made with (> different men, covering- an aggregate of one hundred and 
eighty-four days, the ratio of the potential energy of the material 
oxidized in the bod}- to the energy given otf from the body in the 
forms of heat and muscular work, as measured by the respiration 
calorimeter, is as 1,000 to 99!>. The same ratio of 1,000 to 999 was 
found in the average of a large number of experiments made to test 
the accuracy of the apparatus. Closer agreement than this could not 
be looked for. 

The practical usefulness of this apparatus and method of inquiry 
will be realized more clearly when we consider that it gives us a means 
for measuring more exactl}' than has hitherto been possible, the trans- 
formations of matter and energy which take place in the bodies of 
different persons with different kinds and amounts of food or in fast- 
ing, and under widely varying conditions of muscular and mental 
activity. The experiments furnish a mass of data needed for various 
sciences of physiolog}^ and hygiene. These data have to do with 
food, drink, and excretory products and with the metabolic processes 
and changes of bod}^ tissue as they are influenced by work, sleep, 
diet, temperature, and other circumstances. They show the nutritive 
values of food and the demands of the body in health and disease. 
Incidentally the}^ throw valuable light on problems of ventilation and 
numerous other questions of hygiene. They supply the foundations 
of the doctrine of nutrition and belong to the highest order of scien- 
tific research. 

FACTORS FOR DIGESTIBILITY AND FUEL VALUE OF NUTRIENTS. 

The data obtained in the nutrition investigations ma}' be used in 
deducing certain factors which are useful in various ways to students 
and investigators of similar problems, and to some extent also to those 
who wish to make practical application of the results. Such factors, 
for the digestibility and fuel value of the nutrients of ordinar}- mixed 
diet have been epitomized b}' Professor Atwater in the following 
table: 

31^823— IM- — 2 



Factors for digestibility and fuel value of nutrients in mixed diet. 





Protein. 


Fat. 


Carbohydrate 




i- 




5 ^ 


1 

5 


Fuel value 
per gram. 


5 " 

Si 


1 

5 


Fuel value 
per gram. 


pi 


3 

a 
be 

s 


Fuel value 
per gram. 




materials. 




5S 




II 

5 £ 


il 

Eh 


11 

.£fa 


1 ^^ 

C ^ ^ 


Meal nnd fish 


Pa- 
cent. 
43 

6 


Per 

cent. 

97 

97 

97 


Calor- 
ics. 
4.27 
4.37 


Calor- 
ics. 
4.40 
4.50 


Per 
cent. 

\ 60 

32 


Per 

cent. 
95 
95 


Cator- 

9.03 

8.79 


ffS. 

9.50 
9.25 


Per 
cent. 


Per 
cent. 

98 


Calor- 
ies. 

3.82 


Cator- P?)- 
•es. 1 cent. 

1 87 
3.90 ' S9 


Dairy products 


V> 


4.27 j 4.40 


■ 1 93 


Animal food 
(of mixed 
diet) 


61 


97 


4.27 


4.40 


92 


95 


8.93 


9.40 


5 


98 


3.82 


3. 90 89 


Cereals 


31 


85 

78 


3.87 
3.47 


4.55 
4.45 


r ^ 


90 


8.37 


9.30 


55 

1 

1 21 

"is' 

I 5 


98 
97 
98 
98 
95 
90 


4.11 
4.07 
3.87 
4.11 
3.99 
3.60 


4.20 ! 91 


Legumes (dried) ... 


2 


4.20 
3.95 
4.20 
4.20 
4 00 


83 
98 






98 




5 
1 


83 
85 


3.11 
3. 36 


3.75 




91 


Fruit 


3.95 J 


«.s 








Vegetable 
food (of 
mixeddiet). 


39 


So 


3.74 


4.40 


8 


90 


8.37 


9.30 


95 


97 


4.03 


4.15 


92 


Total food (of 
mixeddiet). 


100 


92 


4.05 


4. 40 100 


95 


8.93 


9.40 


100 


97 


4.03 


4.15 


91 



Briefly stated, on an average about 96 per cent of the total organic 
matter of mixed diet will l)e digested and !)1 per cent of the energy will 
be available to the bod}- or, in other words, the body rejects about 4 
per cent of the nutrients and al)out 9 per cent of the energy supplied 
by the food. 

With the exception of .some important European determinations of 
heats of combustion, the figures given in the above talde are derived 
from late investigations in the United States. These included over 
4,500 analyses of food materials; over 500 dietary .studies; nearly (iOO 
digestion experiments, mostly with men; several thousand determina- 
tionsof heatof combustion of food materials and excretor}" products, and 
CA experiments, covering in the aggregate 184 days, with men in the 
respiration calorimeter, besides a considerable number of other experi- 
mental iiKjiiirics, including especially the determinations of the con- 
stitution of protein compounds in various materials. The results of 
comi)utati()ns by means of these factoivs have been found to agree very 
closely with those obtained in actual experiments, showing that the 
factors are reasonablv accunite. 



THE PECUNIARY ECONOMY OF FOOD. 

The sum expended for food is the princii)al item in the living 
expenses of a large majority of families, and Net very few of e\en the 
most intelligent housekeepers have clear ideas regarding the actual 
nutritive Nalue of difl'erent food materials. Very generally, even those 
who endeavor to economize know little of the combinations which are 
best fitted for nourishment and have still less information as to the 



U. S. Dept. of Agr., Office of Expt. Stations, 71; 



Plate VI. 



protein. 



Fhts 



Carbohydrates 



Fuel Value. 



FOOD MATERIALS 



Prue 

pound 



ec^ 



7V« 

rents 
will 



Xv/€> 



Pounds o{nu,Lritnts aruL talones of^ fuft value in. 10 cenb 
worth. 



lib 



zlbs 



ilbs 



7000 (hi 



foooCai 



6000 Cat/ 



Jlcey, lOAMvd 



i\ , SA.ltOA, 



%ic^ , -a*3ou£cW 



&(i\AJOCav\/, Zi. 



.67> 



<&zXi,X.o 



<z),czM, /aa£t, -|«^ 



e'Ca 1 



^c d)^.\/s\g , £ii/ff^ ,dxcnp,u> 



I CO 



taclftefe , /TAVwic' 



I.YJ 



&v^iXO, ^$ /ta^x-xymvtt' 



.bi I 



a>1l\C& , ^/i(A\Xs ^utvtt' 



'i'-Vcittl 



MO 



tn: 



m 



v^f-'vii:-?! 



\2c\AS , 2t ccivla' .c>a:;cu 



■VSiliatAc.^5 



VSHp^jik/^^c-v^-^. 



1?,. f7 



koo 



(S<vk 'nx.caX. 



: ,^0 



u: 



(Kean'E>, -vefetti . c!tiCi? 



»3a\ 



e'j la loes , SCcent? MtM^hii 



Q>v 



\&Z 



Pecuniary Economy of Food. Amounts of Actually Nutritive Ingredients 
Obtained in Different Food Materials for 10 Cents. 

Amounts of nutrients in pound.s; fuel value in ealories. 



19 

relation between the true nutritive value of foods and tlieir cost. Of 
the different food materials which are palatable, nutritious, and other- 
wise suited for nourishment, the consumer wishes to know what ones 
are pecuniarily the most economical; in other words, which foods fur- 
nish the largest amounts of available nutrients at the lowest cost. In 
answering" this question it is necessary to take into account not only 
the prices per pound, quart, or bushel of the different materials, but 
also the kinds and amounts of the actual nutrients they contain and 
their titness to meet the demands of the l)ody for nourishment. The 
cheapest food is that which supplies the most nutriment for the least 
mone}'. The most economical food is that which is cheapest and at the 
same time best adapted to the needs of the user. 

In nran}" of the nutrition investigations, especially- the dietary stud- 
ies carried on by this Department, the cost of food in relation to the 
nutrients furnished has been considered. Plate VI, which compares 
a number of common foods from a pecuniary standpoint, shows the 
amounts of the protein, fat, carbohydrates, and energy which 10 cents 
worth of each of the food materials selected will supply. In every 
case the assmiied price per pound is an average value based upon a 
considerable amount of data collected in different localities. 

THE EDUCATIONAL INFLUENCE OF THE NUTRITION INVESTIGA- 
TIONS. 

If the piactical usefulness of these investigations is important, the 
educational influence is no less so. This is manifesting itself in a num- 
l)er of wa3's, but most of all in bringing the results of the inquirj' 
directly into schools. Taking all the public schools and the colleges 
in the country together, the number in which the results of these 
inquiries are being directly taught is relatively small. Nevertheless, 
the actual number of institutions in which teachers are including more 
or less of these results in their courses of instruction, especially in phys- 
iology, is numericall}" large and is growing with the most encouraging- 
rapidity. It has been the policy of the Department to deal very gen- 
erously with schools and with teachers in the distribution of nutrition 
publications. Not only in cities, but in rural districts, there is a large 
and rapidl}' growing demand from the schools for these publications. 
The}' appear to meet an actual want — one that has been rather dimly 
felt hitherto, but is now becoming much more detinite. The most active 
call, as would naturally be expected, has been from teachers connected 
with technical schools or the technical departments of colleges and 
high schools. The demand, however, has been almost as great from 
schools of medicine. 

That the time for the development of these inquiries is especially 
opportune is shown by the use made of the results in the teaching of 
what is called domestic economy, or household economics. This rep- 
resents an educational movement of greater import than many I'ealize. 



20 

The movement is coming- in response to popular demand and lias the 
earnest support of many of our leading educators, not a few of whom 
are emphatic in the expression of their belief in the wisdom of the 
popular demand and the possibility of making such instruction very 
useful, especially in courses for girls and young women. Educational 
experience shows that a certain time is required to bring an}' new 
subject lirst into scientific and then into pedagogic form. The science 
of food and nutrition has already assumed reasonal)ly clear and accu- 
rate scientilic form and is being rapidly brought into pedagogic form. 

CONCLUSION. 

One most important feature of these investigations is the coopera- 
tion with scientilic. educational, and philanthropic institutions in so 
many parts of the countr}'. Among the advantages of this method of 
cooperation several are especially worthy of mention. First, there is 
the larger econom}" and effectiveness of scientific eti'orts shown in the 
development of special methods of investigation, in the planning of 
general and special lines of inquiry, and in the comparison and publi- 
cation of results. The cooperating investigators and institutions are 
contributors to the enterprise, and the spirit of cooperation thus 
becomes in itself an important agency for diffusing the results and 
insuring their most useful application. Another advantage is found 
in the fact that, while institutions and investigators have that liberty 
of initiative and action which is so essential for scientilic research, tlie 
several inquiries are so coordinated, and investigators are so aided by 
counsel and b}' the collating of the results of inquiry elsewhere as to 
give both the individual investigations and the research as a whole 
far more influence and usefulness than would otherwise be possible. 
From the practical standpoint also there is an advantage in the fact 
that so many different institutions, representing the varied interests 
of people in widely separate regions, are united in the study of preva- 
lent conditions and in efforts toward improvement. Besides this the 
funds provided b}' the Department are used economical!}' and are 
supplemented by the resources of the institutions and often l)v means 
from other sources. Thus not only is a large amount of Avork being- 
done, but the interest is widel}^ extended and the results are given 
very great practical usefulness. 

So it has come about that from modest beginnings, in which work 
was carried on largely with the aid of private individuals, these inves- 
tigations under the auspices of this Department have assumed a mag- 
nitude quite out of proportion to their actual cost; have achieved a 
noteworthy significance in scientific, educational, sociological, and 
economic results; and by the extensive coo})eration of individuals and 
institutions of various kinds with this Department a large amount of 
valuable work is being done in a systematic way, the results of which 
are made available to the i)ublic. 

O 



LIST OF PUBLICATIONS OF THE OFFICE OF EXPERIMENT STATIONS ON 
THE FOOD AND NUTRITION OF MAN-Continued. 

Bui. 89. Experiments oil the Effect of Muscular Work upon the Digestibility of Food and the Metab- 
olism of Nitrogen. Conducted at the University of Tennessee, 1897-1899. By C. E. Wait. 
Pp. 77. Price, 5 cents. 

Bui. 91. Nutrition Investigations at the University of Illinois, North Dakota Agricultural College, 
and Lake Erie College, Ohio, 189G-1900. By H. S. Grindley ant} J. L. Sammis, E. F. Ladd, 
anil Isabel Be vier and Elizabeth C. Sprague. Pp. 4i2. Price, 5 cents. 

Bui. 98. The Eft'ect of Severe and Prolonged ;Museular Work on Food Consumption, Digestion, and 
Metabolism, by W. O. Atwater and H. C. Sherman, and the Mechanical Work and Efficiency 
of Bicyclers, by R. C. Carpenter. Pp. G7. Price, 5 cents. 

Bui. 101. Studies on Bread and Bread Making at the University of Minnesota in 1899 and 1900, By 
Harry Snyder. Pp. f>5. Price, 5 cents. 

Bui. 102. Experiments on Losses in Cooking Meat, 1898-1900. By H. S. Grindley, with the coopera- 
tion of H. M(tCormack and H. C. Porter. Pp. 64. Price, 5 cents. 

Bui. 107. Nutrition Investigations among Fruitarians and Chinese at the California Agricultural 
Experiment Station, 1899-1901. Bv M. E. Jaffa. Pp.43. Price, 5 cents. 

Bui. 109. Experiments on the ^Metabolism of Matter and Energy in the Human Body, 1898-1900. By 
W. O. Atwater and F. G. Benedict, with the cooperation of A. P. Brvant, A. W. Smith, and 
J. F. Snell. Pp. 147. Price, 10 cents. 

Bui. 116. Dietary Studies in New York City in 1896 and 1897. By W. O. Atwater and A. P. Bryant. 
Pp. 83. Price, 5 cents. 

Bui. 117. Experiments on the Effect of Muscular Work upon the Digestibility of Food and the Metab- 
olism of Nitrogen. Conducted at the University of Tennessee, 1899-1900. By C. E. Wait. 
Pp. 43. Price, 5 cents. 

Bui. 121. Experiments on the Metabolism of Nitrogen, Sulphvir, and Phosphorus in the Human 
Organism. By H. C. Sherman. Pp.47. Price, 6 cents. 

Bui. 126. Studies on the Digestibilitv and Nutritive Value of Bread at the University of Minnesota in 
1900-1902. By Harry Snyder. Pp. .^2. Price, 5 cents. 

Bui. 129. Dietary Studies in Boston and Springfield, Ma.ss., Philadelphia, Pa., and Chicago, 111. By 
Lydia Southard, Ellen H. Richards, Susannah U.sher, Bertha M. Terrill, and Amelia 
Shapleigh. Edited by R. D. Milner. Pp. 103. Price, 10 cents. 

Bui. 132. Further Investigations among Fruitarians at the California Agricultural Experttnent 
Station. By M. E. Jaffa. Pp. 81. Price, ."> cents. 

Bui. 136. Experiments on the Metabolism of Matter and Energy in the Human Body, 1900-1902. By 
W. O. Atwater and F. A. Benedict, with the cooperation of A. P. Bryant, R. D. Milner, and 
PiTul Merrill. Pp. ,3.57. Price, 20 cents. 

Bui. 141. Exjieriments on Losses in Cooking Meat, 1900-1903. By H. S. Grindley and Timothy 
Mojonnier. Pp. 96. Price, 5 cents. 

Bui. 143. Studies on the Digestibility and Nutritive Value of Bread at the Maine Agricultural Experi- 
ment Station, 1899-1903. By C. D. Woods and L. H. Merrill. Pp. 77. Price, 6 cents. 

farmers' bulletins. 

*Bul. 23. Foods: Nutritive Value and Cost. By W. O. Atwater. Pp. 32. 

Bui. 34. Meats: Composition and Cooking. By C. D. Woods. Pp. 29. 

Bui. 74. Milk as Food. Pp. :39. 

Bui. 85. Fish as Food. Bv C. F. Langworthy. Pp. 30. 

Bui. 93. Sugar as Food. • By Marv H. Abel. Pp. 27. 

Bui. 112. Bread and the Principles of Bread Making. By Helen W. Atwater. Pp. 39. 

Bui. 121. Beans, Peas, and other Legumes as Food. By Mary H. Abel. Pp. 32. 

Bui. 128. Eggs and their Uses as Food. Bv C. F. Langworthv. Pp. 32. 

Bui. 142. Principles of Nutrition and Nutritive Value of Food. Bv W. O. Atwater. Pp. 48. 

Bui. 182. Poultry as Food. By Helen Atwater. Pp. 40. 

CIRCUL.VR. 

Cir. 46. The Functions and Uses of Food. By C. F. Langworthy. Pp.10. 

SEPARATES. 

*Food and Diet. By W. O. Atwater. Reprinted from Yearbook of Department of Agriculture for 

1894. Pp. 44. • 

Some ResuKsof Dietary Studies in the ITnited States. By A. P. Bryant. Reprinted from Y'earbook 

of Department of Agriculture for 1S9S. Pp. 14. 
Development of the Nutrition Investigations of the Department of Agriculture. By A. C. True and 

R. D. Milner. Reprinted from Yearbook of Department of Agriculture for 1899. Pp. 16. 
The Value of Potatoes as Food. By C. F. Langworthy. Reprinted from Y'earbook of Department of 

Agricnlmre for 1900. Pp. 16. 
Dietaries in Public Institutions. By W. 0. Atwater. Reprinted from Yearbook of Department of 

Agriculture for 1891. Pp.18. 
The Cost of Food as Related to its Nutritive Value. By R. D. Milner. Reprinted from Yearbook of 

Department of Agriculture for 1902. Pp.19. 
Scope and Results of the Nutrition Investigations of the Office of Experiment Stations. Reprinted 

from Annual Report of the Office of Experiment Stations for the vear ended June 30, 1901. 

Pp. .50. 
Dietary Studies of Groups, Especially in Public Institutions. By C. F. Langworthy. Reprinted from 

Annual Report of the OJBice of Experiment Stations for the year ended June 30, 1902. 

Pp. 34. 




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